261020907 has 32 divisors (see below), whose sum is σ = 467942400. Its totient is φ = 140379264.

The previous prime is 261020861. The next prime is 261020923. The reversal of 261020907 is 709020162.

It is not a de Polignac number, because 261020907 - 2¹¹ = 261018859 is a prime.

It is a super-2 number, since 2×261020907² = 136263827782205298, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (261020957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37407 + ... + 43832.

It is an arithmetic number, because the mean of its divisors is an integer number (14623200).

Almost surely, 2^261020907 is an apocalyptic number.

261020907 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

261020907 is a deficient number, since it is larger than the sum of its proper divisors (206921493).

261020907 is a wasteful number, since it uses less digits than its factorization.

261020907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81272 (or 81266 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 261020907 is about 16156.1414638521. The cubic root of 261020907 is about 639.0847162252.

The spelling of 261020907 in words is "two hundred sixty-one million, twenty thousand, nine hundred seven".